It is known to use a continuous distribution of sound energy, which will be referred to herein as an “acoustic field”, for a range of applications, including haptic feedback.
It is known to control an acoustic field by defining one or more control points in a space within which the acoustic field may exist. Each control point is assigned an amplitude value equating to a desired amplitude of the acoustic field at the control point. Transducers are then controlled to create an acoustic field exhibiting the desired amplitude at each of the control points. When human skin interacts with the acoustic field, vibrations of the skin are interpreted by mechanoreceptors being excited and sending signals to the brain via the nervous system.
When used in mid-air, haptic technology works by focusing sound at an ultrasonic carrier frequency to a point or points in the space above the transducers. Then this is modulated by a low frequency wave that generates the haptic sensation.
Nonetheless, real-world implementation of haptic feedback systems may require processing improvements in order to better simulate desired haptic feedback characteristics in real time. Known systems suffer from limitations, in that it is difficult to account for many control points at once while achieving fast update rates for the state of the transducers, acoustic field and therefore control points. Fast and efficient updates are required for a commercially viable system.
Accordingly, a system that provides various improved processing techniques for haptic feedback is desirable.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.